A third Briton, Junaid Hussain, was killed in a US airstrike six days later, on 24 August, the Prime Minister said.

Mr Cameron defended the RAF raid, telling the Commons it was "necessary and proportionate", adding it was "entirely lawful" and was approved by Attorney General Jeremy Wright.

The PM claimed Khan and Hussain were actively involved in orchestrating a number of plots to attack "high-profile public commemorations" over the summer.

All three were killed in Raqqa, considered the capital of the so-called Islamic State, in Syria.

Mr Cameron told MPs that security chiefs had stopped at least six terror attacks against Britain in the last 12 months, adding the risk to Britain from Islamist extremist violence is "more acute today than ever before".

The RAF strike specifically targeted Khan, but Amin was also killed, along with another man.

Khan travelled to Syria in late 2013, and appeared in a video calling for Westerners to fight in Syria and Iraq.

Sky's Foreign Editor Sam Kiley said all three Britons were well-known to UK security services.

Hussain was a "leading light" in IS's cyber campaign, Kiley said.

But Kiley said attention would undoubtedly turn to whether the deaths are viewed as necessary for self-defence or as "extra-judicial executions".

Mr Cameron told the Commons: "We should be under no illusion. Their intention was the murder of British citizens......

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ATTENTION:Bran is the hottest man on LL
"Im sorry to inform you that your Penis is too mighty for our group Bran. It scares us."[Dwencl]
Paulingrad in the Drone leaving thread...
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